Battery charger



FIG. 1 is a perspective view of the battery charger;

FIG. 2 is a top plan view;

FIG. 3 is a left side elevational view;

FIG. 4 is a front end elevational view;

FIG. 5 is a rear side elevational view;

FIG. 6 is a right end elevational view; and,

FIG. 7 is a bottom plan view. 

The ornamental design for a battery charger, as shown and described. 